animations: Add flutter_animate (#1681)

animations/lib/src/misc/flutter_animate.dart

@@ -0,0 +1,43 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_animate/flutter_animate.dart';
+
+// Demonstrating the `flutter_animate` package
+class FlutterAnimateDemo extends StatelessWidget {
+  static const String routeName = 'misc/flutter_animate';
+
+  const FlutterAnimateDemo({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Flutter Animate Demo'),
+      ),
+      body: Center(
+        child: Padding(
+          padding: const EdgeInsets.all(16),
+          child: Text(
+            "Hello Flutter Animate",
+            style: Theme.of(context).textTheme.headlineLarge,
+          )
+              .animate(
+                onPlay: (controller) => controller.repeat(),
+              )
+              .then(delay: 250.ms)
+              .fadeIn(duration: 500.ms)
+              .then(delay: 250.ms)
+              .shimmer(duration: 400.ms)
+              .then(delay: 250.ms)
+              .slide()
+              .then(delay: 250.ms)
+              .blur(duration: 500.ms)
+              .then(delay: 100.ms),
+        ),
+      ),
+    );
+  }
+}

animations/lib/src/misc/misc.dart

@@ -5,6 +5,7 @@ export 'card_swipe.dart';
 export 'carousel.dart';
 export 'curved_animation.dart';
 export 'expand_card.dart';
+export 'flutter_animate.dart';
 export 'focus_image.dart';
 export 'hero_animation.dart';
 export 'physics_card_drag.dart';